When the camera switches between shots of the treadmill that Rut Ru was running on you can see the back tires off and on the ground.
After Rut Ru gets shot in the butt with the arrow and jumps of the treadmill and the back wheels come off the ground you can see a sandbag.
When the Dudesons are climbing the tree outside the castle you can see the shadow of the SteadyCam.